The present invention relates to smoking articles such as cigarettes, and in particular to the synthesis of a precursor for altering the aroma and flavor characteristics of the mainstream and sidestream smoke of smoking articles.
Popular smoking articles, such as cigarettes, have a substantially rod shaped structure and include a charge of smokable material such as strands or shreds of tobacco (e.g., cut filler) surrounded by a paper wrapper thereby providing a so-called "tobacco rod." Numerous popular cigarettes have cylindrical filter elements aligned in an end-to-end relationship with the tobacco rod. Typically, filter elements are constructed from fibrous materials such as cellulose acetate, have a circumscribing plug wrap, and are attached to the tobacco rod using tipping material.
Cigarettes are employed by the smoker by burning one end thereof. The smoker then receives mainstream smoke into his/her mouth by drawing on the opposite end (e.g., filter end) of the cigarette. Typically, a person using a cigarette draws on or puffs the article about 5 to about 10 times, and each puff lasts about 0.5 second to about 2 seconds. Typically, a burning cigarette has a useful lifetime of about 1 minute to about 10 minutes. During the time that the cigarette is not being drawn upon by the smoker, it remains burning and sidestream smoke can be generated. Sidestream smoke is smoke which directly enters and diffuses into the atmosphere during the burning of a smoking article. The characteristic sight and odor of the mainstream smoke and the sidestream smoke may be perceived negatively by certain individuals.
There are several general approaches to altering the characteristic sight and odor of mainstream and sidestream smoke. One is to reduce the amount of sidestream smoke such as described, for example in U.S. Pat. Nos. 3,744,496 to McCarty, 4,231,377 and 4,420,002 both to Cline and 4,561,454 to Guess. Typically, this is accomplished by reducing the amount of tobacco consumed during the smolder period between puffs, or by reducing the amount of smoke generated during combustion. Another approach is to alter the aroma of the sidestream smoke such as described, for example in U.S. Pat. Nos. 4,941,486 to Dube et al. and 4,804,002 to Herron.
It would be highly desirable to provide a method of forming an aromatic and flavorful precursor useful in a smoking article and components thereof which prior to being employed by the user is odorless, and when employed provides highly pleasant smelling sidestream smoke and which delivers good tobacco taste to the smoker.